This invention broadly relates to coating stripping compositions and methods of removing coatings from surfaces, particularly metals which are subject to corrosion. More specially, the invention relates to removing enamels, acrylic lacquers, zinc chromate primers, epoxy coatings and polyurethane coatings from metals such as aluminum, magnesium, titanium and steel.
In the prior art the methods of removing such compositions from the listed metals have generally involved the use of corrosive materials such as nitric acid, sulfuric acid, chromic acid and hydrofluoric acid and aqueous alkaline solutions. It is apparent that these materials are not only difficult to handle but tend to corrode and deteriorate metals. Therefore, the removal of difficult to remove coatings from metals has formed a particularly difficlt problem for the art. Other paint and resin stripping compositions have relied on various combinations of organic solvents with or without the use of water and with or without alkali metal hydroxides. Patents relating to such stripping compositions and processes are Nos. 2,662,837, 2,710,843, 2,755,209, 2,898,246, 2,940,877, 2,992,995, 3,058,918, 3,216,945, 3,321,407, 3,324,039, 3,322,677, and 3,417,025. These compositions and processes have not been completely satisfactory.
This invention avoids these problems and provides a non-corrosive anhydrous stripping compositions adapted for use in removing coatings such as enamels, acrylics, epoxy, zinc chromate primers, epoxy-polyamide coatings and polylurethane coatings from metals.